Flexible, durable, green thermoelectric composite fabrics for textile-based wearable energy harvesting and self-powered sensing

Textile-based wearable thermoelectric (TE) devices which could realize electricity harvesting and self-powered sensing using body heat attract great attention as they combine flexibility and skin conformality, yet do not require an external power supply. However, the challenge remains in developing durable TE fabrics which could generate sufficient power. Herein, a novel and scalable fabrication strategy that realizes simultaneous carbon nanotube (CNT) electrospray on poly (lactic acid) (PLA) fabric electrospinning is proposed to fabricate flexible TE composite fabrics. The optimal TE fabrics demonstrate a high Seebeck coefficient of 62.9 & PLUSMN; 6.2 & mu;V K-1 and a maximum power density of 37.3 nW cm-2 is achieved at a temperature difference of 17 K with flexible textile TE generator assembled with CNT/PLA TE composite fabrics on neat PLA textile. The device further demonstrated superior capability in electricity harvesting from the human body and self-powered temperature and/or breath sensing. Moreover, the device exhibited excellent durability after 500 times bending and 100 times water dip -wash, which is ascribed to the uniform CNT electrospray among the PLA nanofibers and strong adhesion between the CNT and PLA. This work provides a novel fabrication strategy for green, durable and wearable TE composites and textiles in emerging power generation and smart sensing applications.